heb firefox gereinstalleerd volgens dit plan;
To do a clean install of Firefox, follow these steps:
back up your Firefox bookmarks before you uninstall Firefox
Backing Up Firefox Bookmarks, or
Easier Way to Back Up Firefox Bookmarks, or
Backing Up Your Mozilla, Firefox, Thunderbird and Netscape Profiles
uninstall Firefox
reboot
in Windows Explorer, go to C:\Documents and Settings
if you see the Application Data folder and the Local Settings folder, proceed to step 7
if you don’t see the Application Data folder and the Local Settings folder, you need to unhide hidden files and folders. See my article Showing Hidden Files and Folders.
In the Application Data folder, open the Mozilla folder. Then, rename the Firefox folder — do NOT delete it, this will be a backup that has your bookmarks in it.
In the Local Settings folder, open the Mozilla folder. Then, rename the Firefox folder — do NOT delete it, this will be a backup that has your bookmarks in it. (I don’t think you’ll need this stuff, but rename it just to be sure.)
Download the latest version of Firefox. You might have already done this — if not, now’s a good time.
Install Firefox.
Restore your bookmarks
alles gedaan maar de oudeinstellingen blijven bestaan terwijl ik firefox met revo portable heb verwijderd!. Hoe krijg ik weer een schone firefox op mijn computer?